Re: Need MicroControllers with built in USB Port and Protocol

"Ulf Samuelsson" <ulf@xxxxxxxxxxxxx> wrote in
news:ev0198$ta4$3@xxxxxxxx:

Now you have me interested. What can be the difference between a
mini-host and a "real host". To me it only means that the software is
limited.

...
However, a hub is the most compliant of all devices. How could a hub
not work?


I did not look too closely on this, but I assume that there are
problems in handling multiple streams.
If you connect a hub to the single stream, it is pretty useless, isn't
it?


Well, a hub can be inserted for several reasons. For one it may be
cheaper than an external phy. Also it may have better power control on
its ports. If it is a high speed connection, a full speed device will
never see other communications on its link (assume either multiple TT or
single device on the hub). It may deal with suspend/resume or external
wakeup better.

But in general, you are right a hub between a host and a slave does not
contribute much.

I guess what I was saying is that the difference between single
"streams" (your word) and multiple streams (ie a usb bus) is lack of a
hub driver. However, a hub is the best, most well defined class. If a
hub driver is not provided it is a crippleware package, ie they took
support out of a regular stack to have a "usb lite" package.

Regards, Steve
.

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